This note gives a summary and careful check of concepts to date, and shows that the gyromagnetic ratio as well as the electron g factor depends on the vacuum angular frequency. The relativistic gyromagnetic ratio is given in Eq. (18) for the Zeeman effect in a relativistic particle. Previous calculations of the velocity and mass of the vacuum particle are checked. It is shown that it is possible to develop a new type of scattering theory in which vacuum particles scatter off matter particles and vice versa. So there can be Compton scattering of a photon from the vacuum particle for example. This means that light travelling billions of light years through deep space will be scattered and will become diffuse, scattered apparently off nothing, however the light is scattered by vacuum particles. Given an estimate of the mass of the universe, and the mass of the vacuum particle (about 2 ten power minus 33) the number of vacuum particles in the universe can be calculated. This assumes that the universe is made up overwhelmingly of non visible matter, with galaxies situated in the deep space far apart from each other. The mass of visible matter in the universe (galaxies) is ten power 53 kilograms, which according to same old dogma (sod all or nothing in it) is 20% of the total mass. The rest being made up of “dark matter” and “dark energy” or “missing mass”. The missing mass is therefore 4 x ten power 53 kilograms. So there are about 2 x ten power 86 vacuum particles in the universe. These are all gravitating particles. So dark mass and all that stuff is replaced by the far more sensible vacuum particle. being sensible it is not dogma.